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Dear Users
Our Commercial and Academic users around the world can use these same forums here as before i.e. the Altair Support Forum ,
Commercial users from India with solver queries can go to the Solver Forum for India Commercial Users ,
Academic Users from India and AOC India Participants are requested to go to the Forum for India Academic Users and AOC India Participants ,
We will be tending to all queries in all the forums promptly as before, thank you for your understanding.

Hi,
You can convert the Dyna model into RADIOSS using HyperCrash.
Make sure you are using the latest HyperCrash 17.0 for the best translation. Start HyperCrash and pick the RADIOSS user profile. After HyperCrash starts, go to File>>Import>>Ls Dyna, and select your Dyna model. During import HyperCrash will convert the model to RADIOSS model..

Please go through the RADIOSS user guide ( http://forum.altairhyperworks.com/index.php?/topic/20652-radioss-2017-reference-manual-documents-user-guide-and-tutorials/) where the stiffness formulation is shown.
This error message on "Infinite domain detected" may appear during sorting of contact interfaces when the distance between some nodes of the model becomes infinite. One has to look at the model behavior to understand why some node coordinates are infinite.One common explanation is "flying" nodes after failure of elements belonging to interface surfaces. In this case using Idel =2 in contact interfaces should fix this problem.

Hi Kin Poh,
This is license related issue. More HyperWorks Units (HWU) of Altair allows customers to access an entire suite of products as well as many partner products.
I recommend you to get in touch with the local Altair support team so that they can help you in increasing the HyperWorks units.

Hi Kin Poh,
The negative volume issue happens when the solid elements are very deformed and their characteristic length goes to 0. For large strain formulation the time step of an element goes to 0 when the element is compressed. Those elements will be automatically switched to small strain.
Regarding negative stiffness node this error could be of different reasons.
Is these nodes involved in a TYPE2 interface?. If so, please remove these nodes from the slave side of your TYPE2 interface. Else, you can try with Spotflag =1 also for the interface.

Hi Kartik,
For spring elements you will not get stress output.
If you have a exact spring stiffness value you can simulate it without much unstable model behavior.
I varied the spring stiffness value and imposed displacement was provided. Attaching the same file for your reference.
This error happens when the solid elements are very deformed and their characteristic length goes to 0. For large strain formulation the time step of an element goes to 0 when the element is compressed. From RADIOSS 2017 version those elements will be automatically switched to small strain.
v5-8-geo_0000.rad

Hi Kin Poh,
If you can send the out files we can help you in sorting the errors. Always run the model checker (Tools>>ModelChecker>>RADIOSSblock) so that HyperMesh will list out the possible modelling errors.
You can check the Frequently Asked Questions in our Help Menu where we have some common errors in RADIOSS.
Else you can download our RADIOSS ebook where we have documented common errors (including FAQ's from Help) topic wise.
You can download the ebook from Introduction to Explicit Analysis using RADIOSS

Hi Kin Poh,
The rigid body turns more than one radian per cycle. This situation is due to divergence in the computation.
Please select this rigid body from RBODY MANAGER in HyperMesh and make Ispher to 1.
Let us know whether it helps.

Hi Kartik,
In pulley component collector you have spring elements. Delete those spring elements from pulley collector.
And please note that no material will be assigned for springs. Remove the material from rope component collector.

Hi,
For shell meshing the element thickness specified by the user is assigned half on the element top and half on the bottom side and so it appears as you shown in the above image.
It's only a visualization case and will not affect your analysis, and please continue with your analysis.

Hi Kartik,
I recommend you to try modelling the rope with spring elements. And use the /INTER/TYPE7 (node to surf) and maybe need also use the TYPE11 (edge to edge) as contact interface.
In your case as one end is fixed and you are pulling the other end the model is behaving like this. Try with spring elements and let's review the results.

Hi Toan,
For *undohistorystate please give the count also, and based on this count it undoes one or more history states.
That is if three times you have used *replacenodes, then *undohistorystate 3 which will undo the 3 history states at once. Please try with this.

Hi Andres,
This seems to be an issue with the local system defined.
Go to card edit option and select 'systs' and select the local system referenced for the /INIVEL/AXIS and click on edit.
In the card edit panel select the type as Frame, and run the analysis.